Introduction Qualitative movement screening tools have been developed across several activities, aiming to identify mechanical patterns associated with potential injury risk. Although sprint running mechanics are thought to influence hamstring strain injuries (HSI), there are currently no field-based screening tools available allowing quick assessment. Therefore, this study aimed to determine the intra- and inter-tester reliability of a novel, easy-to-use qualitative screening tool assessing sprint running mechanics (The Sprint Mechanics Assessment Score [S-MAS]).

Materials and Methods The S-MAS is a 12-item scoring tool, developed following a literature review of biomechanical parameters associated with HSI and consultation with sprint coaches.

Slow-motion videos were collected from 36 elite football players (18 female, 18 male) performing maximal velocity sprints.

Two assessors, blinded to each other’s results, independently scored all videos. One assessor (blinded to testing session one scores) scored the same videos in a randomised order 1 week later.

Results Interclass correlation coefficients showed good intra-tester (ICC = .828, 95%CI = .688-.908) and inter-tester (ICC = .799, 95%CI = .642-.892) reliability for overall S-MAS with a standard error of 1 point. Intra-tester and inter-tester percentage agreements for individual items ranged from 75–88% and 66–89% respectively. No significant sex (p = .597) or inter-limb (p = .094) differences were observed for overall score.

Conclusion The S-MAS is a reliable tool assessing sprint running mechanics in both male and female footballers. The easy-to-use nature of the S-MAS means it can be integrated into practice, providing an in-field method of screening sprint mechanics commonly associated with HSI.